com.conveyal.object_differ

Class ObjectDiffer

java.lang.Object

com.conveyal.object_differ.ObjectDiffer

public class ObjectDiffer
extends Object

Perform a recursive deep comparison of objects. This is intended for testing that graph building is reproducible and serialization restores an identical graph. It should be kept relatively simple. Each instance should be used for only one comparison and thrown away. It is not threadsafe. The instance holds configuration and state internally. TODO enforce single usage and/or provide a reset method so ObjectDiffers can be reused. The object differ started out as a copy of the one supplied by csolem via the Entur OTP branch at https://github.com/entur/OpenTripPlanner/tree/protostuff_poc but has been mostly rewritten at this point.

Field Summary

Fields

Modifier and Type	Field and Description
protected Set<Class>	ignoreClasses
protected Set<String>	ignoreFields
protected Set<Class>	useEquals

Constructor Summary

Constructors

Constructor and Description
ObjectDiffer()

Method Summary

Modifier and Type	Method and Description
void	compareTwoObjects(Object a, Object b) This is the main entry point to compare two objects.
void	enableComparingIdenticalObjects() Tell the Differ to execute the whole comparison procedure even when comparing two identical object references.
boolean	hasDifferences()
void	ignoreClasses(Class... classes) Classes of objects whose contents will not be examined.
void	ignoreFields(String... fields) Field names to ignore on all objects.
void	printSummary()
void	skipTransientFields() Tell the Differ to completely skip fields marked transient.
void	useEquals(Class... classes) Use equals to compare instances of these classes.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ignoreFields

protected Set<String> ignoreFields

ignoreClasses

protected Set<Class> ignoreClasses

useEquals

protected Set<Class> useEquals

Constructor Detail

ObjectDiffer

public ObjectDiffer()

Method Detail

enableComparingIdenticalObjects

public void enableComparingIdenticalObjects()

Tell the Differ to execute the whole comparison procedure even when comparing two identical object references. Normally such comparisons would be optimized away since they are by definition identical trees of objects. However this is useful in tests of the comparison system itself - there are known to be no differences.

skipTransientFields

public void skipTransientFields()

Tell the Differ to completely skip fields marked transient. The differ will not see any changes introduced when reconstructing these fields after loading. This is useful though if the transient fields are not reconstructed, or look very different after reconstruction. NOTE this will completely skip over the values in some external library classes like TIntIntMap

ignoreFields

public void ignoreFields(String... fields)

Field names to ignore on all objects.

ignoreClasses

public void ignoreClasses(Class... classes)

Classes of objects whose contents will not be examined. We will still check that two classes of this same type exist in the object graph, but not compare their contents. Currently does not include subclasses, an exact match of the concrete type is necessary.

useEquals

public void useEquals(Class... classes)

Use equals to compare instances of these classes. Currently does not include subclasses, an exact match of the concrete type is necessary.

compareTwoObjects

public void compareTwoObjects(Object a,
                              Object b)

This is the main entry point to compare two objects. It's also called recursively for many other complex objects in the tree.

hasDifferences

public boolean hasDifferences()

printSummary

public void printSummary()